Title: Testing the Principles and Functionality of #87 Differential Protection Relays with Relay Testers

Electric power systems rely on a variety of protection relays to keep them safe and secure from potential equipment damage or failure. One of the most important of these relays is the #87 Differential Protection Relay, which monitors the difference in currents between two points in a system to identify any internal faults or disruptions. To ensure that these relays are functioning properly, modern electrical testing equipment, such as relay testers, are essential.

In this article, we will explore the testing principles and procedures of #87 Differential Protection Relays using the Relay Testers. Specifically, we will focus on the Nari Line Protection and Main Transformer Protection Devices as examples. 

 

Protection Principles:

The #87 Differential Protection Relay operates through the principle of identifying an imbalance in the current flow between two points of a system. It recognizes these imbalances by measuring and comparing the currents from both points, typically using a current transformer. If a significant difference in the two current levels is observed, the relay activates to protect the system from potential equipment damage.

 

Testing Principles:

The testing of a #87 Differential Protection Relay focuses on ensuring that it can effectively identify current imbalances and duly provide protection. Relay test equipment such as Omicron's CMC 356 relay tester can simulate different fault conditions and, with advanced digital processing and analysis, troubleshoot relay relays or the systems they are protecting. 

 

Testing Connection:

Testing the relay involves disconnecting it from the power system and simulating various fault conditions using a relay tester. Applying a current signal to the relay under test and comparing the output with the input allows for the evaluation of the proper functionality of the relay. 

 

Testing Process:

The testing process begins by verifying the connection of the relay to the relay test equipment and then setting up the test parameters. The relay tester then simulates fault conditions and measures whether the relay is correctly identifying and responding to such faults. The test then repeats with multiple fault conditions to cover all potential scenarios.

 

Test Results & Analysis:

The test results will be in the form of tables and charts, which outline how well the relay is performing under different fault conditions. A comprehensive analysis of these results can identify areas where the relay may have failed and enable modifications to improve performance.

 

Conclusion:

 

Electrical protection systems require high accuracy and reliability, and relay testers provide an efficient and effective way of troubleshooting potential problems. The differential protection relay #87 that protects line equipment and Transformers are valuable components of power systems. Testing these protection relays regularly is crucial to maintain their functionality and ensure their ability to safeguard the electrical systems against various kinds of faults. The relay testers such as the CMC 356 of Omicron are capable of testing the performance of relays effectively and efficiently.